what does it mean expiration???

Aids is growing fastest in the poorest countries of africa. these nations don’t have enough doctors, medical labs, or money for medicine. a recent study showed that only a small percentage of hiv-infected children in africa are getting any medical treatment at all. what central idea is emphasized in both sources? the hiv/aids epidemic in africa is serious. the hiv/aids epidemic in south africa is serious. the hiv/aids epidemic among african children is serious. the hiv/aids epidemic among south african children is serious